/* Copyright (c) 2020 XEPIC Corporation Limited */
/*
 * Copyright (c) 2011 Stephen Williams (steve@icarus.com)
 *
 *    This source code is free software; you can redistribute it
 *    and/or modify it in source code form under the terms of the GNU
 *    General Public License as published by the Free Software
 *    Foundation; either version 2 of the License, or (at your option)
 *    any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA.
 */

#include "netstruct.h"

#include <iostream>

#include "ivl_assert.h"
#include "netlist.h"
#include "netvector.h"

using namespace std;

netstruct_t::netstruct_t() : union_(false), packed_(false) {}

netstruct_t::~netstruct_t() {}

void netstruct_t::union_flag(bool flag) {
  // This MUST be called before any members are pushed into the
  // definition. This is because the append relies on this flag
  // being accurate.
  ivl_assert(*this, members_.empty());
  union_ = flag;
}

void netstruct_t::packed(bool flag) {
  ivl_assert(*this, members_.empty());
  packed_ = flag;
}

void netstruct_t::append_member(Design* des, const netstruct_t::member_t& val) {
  ivl_assert(*this, val.net_type);

  members_.push_back(val);
  if (packed_) {
    if (!members_.back().net_type->packed()) {
      cerr << get_fileline() << ": error: "
           << "Member " << members_.back().name << " of packed struct/union"
           << " must be packed." << endl;
      des->errors += 1;
    }
  }
  if (union_ && packed_ && members_.size() > 1) {
    unsigned long expect_wid = members_.front().net_type->packed_width();
    unsigned long got_wid = members_.back().net_type->packed_width();
    if (expect_wid != got_wid) {
      cerr << get_fileline() << ": error: "
           << "Member " << val.name << " of packed union"
           << " is " << got_wid << " bits, expecting " << expect_wid << " bits."
           << endl;
      des->errors += 1;
    }
  }
}

const netstruct_t::member_t* netstruct_t::packed_member(
    perm_string name, unsigned long& off) const {
  unsigned long count_off = 0;
  for (size_t idx = members_.size(); idx > 0; idx -= 1) {
    if (members_[idx - 1].name == name) {
      off = count_off;
      return &members_[idx - 1];
    }
    // If this is not a union, then the members are lined up
    // from LSB to MSB.  If this is a union, then all
    // members are at offset 0.
    if (!union_) count_off += members_[idx - 1].net_type->packed_width();
  }

  return 0;
}

long netstruct_t::packed_width(void) const {
  if (!packed_) return -1;

  // If this is a packed union, then all the members are the
  // same width, so it is sufficient to return the width of any
  // single member.
  if (union_) return members_.front().net_type->packed_width();

  // The width of a packed struct is the sum of member widths.
  long res = 0;
  for (size_t idx = 0; idx < members_.size(); idx += 1)
    res += members_[idx].net_type->packed_width();

  return res;
}

vector<netrange_t> netstruct_t::slice_dimensions() const {
  vector<netrange_t> tmp;
  tmp.push_back(netrange_t(packed_width() - 1, 0));
  return tmp;
}

ivl_variable_type_t netstruct_t::base_type() const {
  if (!packed_) return IVL_VT_NO_TYPE;

  for (size_t idx = 0; idx < members_.size(); idx += 1) {
    if (members_[idx].data_type() != IVL_VT_BOOL)
      return members_[idx].data_type();
  }

  return IVL_VT_BOOL;
}
